Setting up Kyverno & Kyverno Policies

Kyverno and its extension, kyverno-policies, help manage Kubernetes security policies which appear in Kyverno as Kubernetes resources.

To integrate Kyverno & Kyverno Policies into Managed Service for Kubernetes:

1. Install Kyverno & Kyverno Policies.
2. Check how the policy works for the baseline profile.
3. Create and test your own Kyverno policy.

If you no longer need the resources you created, delete them.

Required paid resourcesRequired paid resources

The support cost for this solution includes:

• Fee for using the master and outgoing traffic in a Managed Service for Kubernetes cluster (see Managed Service for Kubernetes pricing).
• Fee for using computing resources, OS, and storage in cluster nodes (VMs) (see Compute Cloud pricing).
• Fee for a public IP address assigned to cluster nodes (see Virtual Private Cloud pricing).

Getting startedGetting started

1. Create a Managed Service for Kubernetes cluster and node group.

   Manually

   Terraform

   1. If you do not have a network yet, create one.

   2. If you do not have any subnets yet, create them in the availability zones where the new Kubernetes cluster and node group will reside.

   3. Create security groups for the Managed Service for Kubernetes cluster and its node groups.

      Warning

      The configuration of security groups determines the performance and availability of the cluster and the services and applications running in it.

   4. Create a Managed Service for Kubernetes cluster and node group with any suitable configuration. When creating, specify the preconfigured security groups.

   1. If you do not have Terraform yet, install it.

   2. Get the authentication credentials. You can add them to environment variables or specify them later in the provider configuration file.

   3. Configure and initialize a provider. There is no need to create a provider configuration file manually, you can download it.

   4. Place the configuration file in a separate working directory and specify the parameter values. If you did not add the authentication credentials to environment variables, specify them in the configuration file.

   5. Download the k8s-cluster.tf cluster configuration file to the same working directory. This file describes:

      • Network.

      • Subnet.

      • Managed Service for Kubernetes cluster.

      • Service account for the Managed Service for Kubernetes cluster and node group.

      • Security groups which contain rules required for the Managed Service for Kubernetes cluster and its node groups.

        Warning

        The configuration of security groups determines the performance and availability of the cluster and the services and applications running in it.

   6. Specify the following in the configuration file:

      • Folder ID.
      • Kubernetes version for the Managed Service for Kubernetes cluster and node groups.
      • Kubernetes cluster CIDR.
      • Service account name. It must be unique within the folder.

   7. Make sure the Terraform configuration files are correct using this command:

      terraform validate
      

      Terraform will show any errors found in your configuration files.

   8. Create the required infrastructure:

      1. Run this command to view the planned changes:

         terraform plan
         

         If you described the configuration correctly, the terminal will display a list of the resources to update and their parameters. This is a verification step that does not apply changes to your resources.

      2. If everything looks correct, apply the changes:

         1. Run this command:

            terraform apply
            

         2. Confirm updating the resources.

         3. Wait for the operation to complete.

      All the required resources will be created in the specified folder. You can check resource availability and their settings in the management console.

2. Install kubect and configure it to work with the new cluster.

Install Kyverno & Kyverno PoliciesInstall Kyverno & Kyverno Policies

Follow this guide to install Kyverno & Kyverno Policies with the following settings:

• Pod Security Standard profile: baseline.
• Validation failure action: enforce.

The baseline Pod Security Standard profile already contains a minimum restriction policy that prevents known privilege abuses.

Check how the policy works for the baseline profileCheck how the policy works for the baseline profile

• Create the nginx pod with standard settings:

  kubectl run nginx --image nginx
  

  Result:

  pod/nginx created
  

  Such a pod satisfies the policy requirements for the baseline profile.

• Create the nginx pod in privileged mode:

  kubectl run nginx --image nginx --privileged=true
  

  Result:

  Error from server: admission webhook "validate.kyverno.svc-fail" denied the request:
  
  policy Pod/default/nginx for resource violation:
  
  disallow-privileged-containers:
    privileged-containers: 'validation error: Privileged mode is disallowed. The fields
      spec.containers[*].securityContext.privileged and spec.initContainers[*].securityContext.privileged
      must be unset or set to `false`. rule privileged-containers failed at path /spec/containers/0/securityContext/privileged/'
  

  The policy rules for the baseline profile prohibit creating pods in privileged mode.

Create and test your own Kyverno policyCreate and test your own Kyverno policy

1. Create a policy that requires all pods to have the app.kubernetes.io/name label:

   1. Save the ClusterPolicy specification to a YAML file named policy.yaml:

      apiVersion: kyverno.io/v1
      kind: ClusterPolicy
      metadata:
        name: require-labels
      spec:
        validationFailureAction: Enforce
        rules:
        - name: check-for-labels
          match:
            any:
            - resources:
                kinds:
                - Pod
          validate:
            message: "label 'app.kubernetes.io/name' is required"
            pattern:
              metadata:
                labels:
                  app.kubernetes.io/name: "?*"
      

   2. Run this command:

      kubectl apply -f policy.yaml
      

      Result:

      clusterpolicy.kyverno.io/require-labels created
      

2. (Optional) Install Policy Reporter in your Managed Service for Kubernetes cluster to be able to save and process policy results.

Test Kyverno & Kyverno PoliciesTest Kyverno & Kyverno Policies

• Create the nginx pod with no app.kubernetes.io/name Kubernetes label:

  kubectl run nginx --image nginx
  

  Result:

  Error from server: admission webhook "validate.kyverno.svc-fail" denied the request:
  resource Pod/default/nginx was blocked due to the following policies
  
  require-labels:
    check-for-labels: 'validation error: label ''app.kubernetes.io/name'' is required.
      Rule check-for-labels failed at path /metadata/labels/app.kubernetes.io/name/'
  

• Create the nginx pod with the app.kubernetes.io/name label:

  kubectl run nginx --image nginx --labels app.kubernetes.io/name=nginx
  

  Result:

  pod/nginx created
  

Delete the resources you createdDelete the resources you created

Some resources are not free of charge. Delete the resources you no longer need to avoid paying for them: